Answer:
168
Step-by-step explanation:
Multiply normally don't even look at the decimal point then look at how many numbers are after the decimal point after multiplying, then the many times the numbers are after the decimal point in both numbers you will place that decimal point that many places FROM the RIGHT.
Download photo math and put the problem into it it will solve it
X²+y²-2y=7
using the formula that links Cartesian to Polar coordinates
x=rcosθ and y=r sin θ
substituting into our expression we get:
(r cos θ)²+(r sin θ)²-2rsinθ=7
expanding the brackets we obtain:
r²cos²θ+r²sin²θ=7+2rsinθ
r²(cos²θ+sin²θ)=7+2rsinθ
using trigonometric identity:
cos²θ+sin²θ=1
thus
r²=2rsinθ+7
Answer: r²=2rsinθ+7
Number 15 is c and number 16 is a